1. Field of the Invention
The present invention relates to methods of manufacturing wire ropes and designs of wire rope twisting machines.
2. Description of the Prior Art
Widely known in the prior art is a method of manufacturing wire ropes in which wires of round section fed from reels are imparted, before their twisting around a core member, with a residual deformation along a helical line. To this end, each wire is given a translational motion and a rotary motion about its geometrical axis and then the wire is bent on supports installed in succession. The deformed wires are twisted around a core member, reduced, pulled and the resulting wire rope is wound on a drum.
Also widely known in the prior art is a wire rope twisting machine which effects the method heretofore described. This machine comprises the following units installed in succession: a drum with a core member wound thereon; a rotor with reels installed on a hollow shaft through which the core member is passed; a body carrying supports rounded by wires and secured on an output portion of the hollow shaft coaxially therewith; a reducing die in which the deformed wires are twisted around the core member and reduced; a pull mechanism and a take-up drum for winding of the wire rope.
To obtain a residual deformation along the helical line, each wire is simultaneously given an axial rotation and a translational motion with a helical bending on the supports. To provide an axial rotation of the wire, each reel is installed in a revolving support on a frame. The frame is installed on its own revolving supports in the rotor. The axis of rotation of the frame is disposed perpendicularly to the axis of rotation of the reel. All the frames are kinematically associated with a drive for rotating them relative to their own supports.
The heretofore described wire rope twisting machine effecting the widely known method is comparatively complicated in design due to installation of the reels in positively revolved frames. This leads to an increase in the overall dimensions and weight of the rotor which in its turn limits the rotational speed thereof and output of the machine as a whole. In addition, such a machine demands a substantial consumption of power.
Known in the prior art is a method of manufacturing wire ropes in which a residual deformation along the helical line is imparted to each wire in the following way: in the process of its translational motion from the reel each wire is bent in a loop which is rotated about the axis of the wire, thereby imparting thereto a required axial rotation when it leaves the loop with a plastic twisting of the wire when it enters the loop; further the wire during its translational motion and rotary motion relative to its geometrical axis is bent on supports (cf. USSR Inventor's Certificate No. 859,513, published on Aug. 30, 1981). As to the rest, the method is similar to that described hereinabove.
Also known in the prior art is a wire rope twisting machine which comprises units installed in succession; a drum with a core member wound thereon; a rotor carrying reels with wire and mounted on a hollow shaft through which the core member is passed; a device for imparting a residual deformation to the wires, secured on an output portion of the hollow shaft coaxially therewith; a reducing die in which the deformed wires are twisted around the core member and reduced; and a pull mechanism and a take-up drum for a wire rope.
A device for imparting a residual deformation to wires comprises a body with hollow shafts installed thereon along the periphery the number of which corresponds to the number of wires to be twisted, and a support for bending each wire. The hollow shafts are kinematically associated with a drive for their rotation. An input portion of each hollow shaft is provided with a fork in which on an axle offset relative to the axis of the hollow shaft is installed a roller adapted for free rotation. This roller serves for bending in a loop the translationally moving wire which further passes through a center hole of the hollow shaft.
Positive rotation of the hollow shaft with the roller and hence of the wire loop surrounding the roller effects a continuous plastic twisting of the wire before it rounds the roller and provides rotation of this wire about its geometrical axis when it leaves the roller, required for imparting the residual deformation to the wire along the helical line.
Further the wire rounds the supports, thereby obtaining the required residual deformation along the helical line (cf. USSR Inventor's Certificate No. 730,906, published on Apr. 30, 1980).
The heretofore described wire rope twisting machine effecting the known method is also comparatively complicated in design.
For imparting an axial rotation to the wire, the latter is bent in a loop on the roller. To impart the residual deformation with a required accuracy to each wire along the helical line, its bending in a loop is accomplished with as great a degree of the elastic deformation as is practically possible. This is effected on a roller of comparatively large dimensions, which serves for bending the wire in a loop. Large dimensions of rollers increase the overall dimensions of the body which mounts these rollers together with the hollow shafts which complicates the drive for rotation of the hollow shafts and the design of the device as a whole. The large overall dimensions of the device for imparting a residual deformation to wires along the helical line respectively increase the mass of revolving parts of the rope twisting machine rotor. This limits the rotor speed and the output of the wire rope twisting machine as a whole. In addition, such a design of the wire rope twisting machine demands a substantial consumption of power.